In order to exchange messages with each other, applications running on different computing devices in a communication network may make use of application-layer connectivity provided by a connectivity fabric of that communication network. At the transport layer, messages exchanged by such applications may be segmented, and the segments may be encapsulated in packets for transmission. A computing device receiving a message addressed to a recipient application running on that computing device may need to confirm that it has received all of the packets in which segments of the message have been encapsulated and notify the recipient application that the transfer of the message is complete.